Материал: m083700e

The WAGO-I/O-SYSTEM 750 • 31

Power Supply

2.7.5 Supply example

Note

The system supply and the field supply should be separated in order to ensure bus operation in the event of a short-circuit on the actuator side.

L1

L2

L3

N

PE

Shield (screen) bus

Main ground bus

230V

24V

a) Power Supply

on coupler / controller via external Supply Module

b) Internal System Supply Module c) Supply Module

passive

d) Supply Module with fuse carrier/ diagnostics

WAGO-I/O-SYSTEM 750

CANopen

32 • The WAGO-I/O-SYSTEM 750

Power Supply

2.7.6 Power Supply Unit

The WAGO-I/O-SYSTEM 750 requires a 24 V direct current system supply with a maximum deviation of -15% or +20 %.

Recommendation

A stable network supply cannot be taken for granted always and everywhere. Therefore, regulated power supply units should be used in order to guarantee the quality of the supply voltage.

A buffer (200 µF per 1 A current load) should be provided for brief voltage dips. The I/O system buffers for approx 1 ms.

The electrical requirement for the field supply is to be determined individually for each power supply point. Thereby all loads through the field devices and bus modules should be considered. The field supply as well influences the bus modules, as the inputs and outputs of some bus modules require the voltage of the field supply.

Note

The system supply and the field supply should be isolated from the power supplies in order to ensure bus operation in the event of short circuits on the actuator side.

WAGO-I/O-SYSTEM 750

CANopen

The WAGO-I/O-SYSTEM 750 • 33

Grounding

2.8 Grounding

2.8.1 Grounding the DIN Rail

2.8.1.1 Framework Assembly

When setting up the framework, the carrier rail must be screwed together with the electrically conducting cabinet or housing frame. The framework or the housing must be grounded. The electronic connection is established via the screw. Thus, the carrier rail is grounded.

Attention

Care must be taken to ensure the flawless electrical connection between the carrier rail and the frame or housing in order to guarantee sufficient grounding.

2.8.1.2 Insulated Assembly

Insulated assembly has been achieved when there is constructively no direct conduction connection between the cabinet frame or machine parts and the carrier rail. Here the earth must be set up via an electrical conductor.

The connected grounding conductor should have a cross section of at least 4 mm2.

Recommendation

The optimal insulated setup is a metallic assembly plate with grounding connection with an electrical conductive link with the carrier rail.

The separate grounding of the carrier rail can be easily set up with the aid of the WAGO ground wire terminals.

WAGO-I/O-SYSTEM 750

CANopen

34 • The WAGO-I/O-SYSTEM 750

Grounding

2.8.2 Grounding Function

The grounding function increases the resistance against disturbances from electro-magnetic interferences. Some components in the I/O system have a carrier rail contact that dissipates electro-magnetic disturbances to the carrier rail.

Attention

Care must be taken to ensure the direct electrical connection between the carrier rail contact and the carrier rail.

The carrier rail must be grounded.

For information on carrier rail properties, please see chapter 2.6.3.2.

WAGO-I/O-SYSTEM 750

CANopen

The WAGO-I/O-SYSTEM 750 • 35

Grounding

2.8.3 Grounding Protection

For the field side, the ground wire is connected to the lowest connection terminals of the power supply module. The ground connection is then connected to the next module via the Power Jumper Contact (PJC). If the bus module has the lower power jumper contact, then the ground wire connection of the field devices can be directly connected to the lower connection terminals of the bus module.

Attention

Should the ground conductor connection of the power jumper contacts within the node become disrupted, e.g. due to a 4-channel bus terminal, the ground connection will need to be re-established.

The ring feeding of the grounding potential will increase the system safety. When one bus module is removed from the group, the grounding connection will remain intact.

The ring feeding method has the grounding conductor connected to the beginning and end of each potential group.

Attention

The regulations relating to the place of assembly as well as the national regulations for maintenance and inspection of the grounding protection must be observed.

WAGO-I/O-SYSTEM 750

CANopen